There are many situations, particularly in biomedical devices, where it is necessary to make an electrical connection between an extremely fine gauge wire (of the order of 0.0015" diameter) and a connector assembly in which the usual soldering technique for electrical connection is inappropriate for any one of a number of reasons. The wires may be made of an alloy which is not wetted by solder, or from an alloy that melts at soldering temperatures or dissolves into the solder. The connection may be implanted in the body or exposed to water vapour which will result in solder corrosion, possible electromechanical failure or heavy metal poisoning. The insulation on the wires may melt or the spacing between the connections or access to them is too restricted to apply solder and a hot iron. Mechanical crimping is the usual alternative, but this too has its limitations. Special materials and/or tools may be required and access space for those tools may be too limited. Crimping may also impose mechanical stress or distortion on the wire predisposing it to failure at the crimp site. Reverse crimping is one solution and attention is directed to U.S. Pat. Nos. 4,828,351 and 3,600,501 which describe connectors in which cylindrical powdered or sintered metal inserts are inserted into the connector hole and the wire to be attached is axially inserted into the insert. A longitudinal force is then applied to the insert in order to expand it radially and thus secure the wire to the connector. When dealing, however, with wires of the order of 0.0015" diameter, or something less than the diameter of a human hair, it is extremely difficult to thread the wire through the axial bore of an insert. It is also extremely difficult to radially expand an insert of the required diameter without damaging the wire. Methods descrbed in the prior art require several complex components and mechanical fixtures and appliances that are difficult to fabricate and to use when working at this fine scale. There is, therefore, a need for an alternative "reverse-crimp" method for securing very fine wires into a connector, particularly for use in implantable devices such as a chchlear prosthesis and the like.